Bloat, or stomach distension, is a dangerous condition in dogs that may progress to a life-threatening condition called gastric dilatation and volvulus (GDV), in which the enlarged stomach twists on itself. Read on to learn more about GDV in dogs.
What Is Bloat in Dogs?
Bloat is a condition in which a dog’s stomach becomes distended with gas or excess food material and enlarges significantly beyond its normal size.
Some affected dogs will develop stomach enlargement only, but some dogs will also develop a condition called gastric dilatation and volvulus (GDV).
GDV is a life-threatening condition in which the bloated stomach rotates on its own axis, blocking both its entrance and exit and preventing the passage of gas and food contents.
The rotation also cuts off the stomach’s blood supply, causing tissue damage or death and producing a buildup of toxins that enter the bloodstream.
The stomach may become so large that it ruptures, pushes on the diaphragm to cause difficulty breathing, and/or compresses the caudal vena cava, a large vein in the abdomen carrying blood from the body back to the heart.
Without this blood returning to the circulation, the dog’s blood pressure drops, and organs become low on oxygen and start to fail.
Low blood pressure, lack of oxygen, and toxins in the bloodstream can cause the dog to go into shock and die if GDV is not treated right away.
Causes of GDV in Dogs
The cause of GDV in dogs is not yet known. However, this condition is most often seen in deep-chested large and giant breeds of middle to older age.
Factors that increase the risk of GDV include rapid ingestion of large amounts of food or water, once-daily meals, exercise shortly after eating, and a thin body condition.
Eating from elevated food bowls and eating dry dog foods with oils or fats listed in the first 4 ingredients may also be risk factors. GDV may develop most commonly 2-3 hours after ingestion of a large meal but can occur at any time.
Dogs prone to stress, anxiety, fearfulness, or aggression, and dogs whose parents or siblings have had GDV are also more likely to develop the condition.
Symptoms of GDV in Dogs
The symptoms of GDV may be mild at first and become more severe as the condition progresses.
Initial symptoms can include non-productive retching, where the dog tries to vomit unsuccessfully, and excessive drooling, panting, and restlessness. Distension of the abdomen may be present initially or develop over time.
As the condition worsens, dogs may become lethargic and weak with pale gums and may collapse or be found recumbent. Severely affected dogs may have trouble breathing.
Diagnosing GDV in Dogs
On initial examination, veterinarians may suspect bloat or GDV based on a dog’s breed and telltale symptoms such as non-productive retching and abdominal distension.
However, x-rays are always recommended to confirm the diagnosis, to determine whether the dog has bloat versus GDV, and to look for evidence of damage to the stomach or spleen.
X-rays are the only way to distinguish bloat from the more life-threatening GDV, as this cannot be determined on physical exams.
In addition, blood tests are recommended to check red blood cell count, electrolytes, and markers of internal organ health and function, which help to determine how significantly a dog’s overall health has been compromised by the GDV.
Dogs with severe abnormalities may have a poorer prognosis for survival, require more intensive care before and after surgery, need additional treatments, and/or require specific monitoring during their recovery period.
Veterinarians will also monitor a dog’s blood pressure, as this can drop as GDV progresses or as dogs go into shock.
Lastly, electrocardiogram (EKG) monitoring is recommended to check for dangerous abnormal heart rhythms, which can occur due to low oxygen levels or toxins in the bloodstream.
Treatment of GDV in Dogs
GDV is considered a life-threatening emergency because it can cause permanent organ damage, shock, and death within hours and is fatal if not treated.
Normal blood flow must be restored to the body, and the pressure in the stomach relieved urgently to prevent life-threatening complications.
Treatment of GDV involves initial stabilization with large amounts of intravenous (IV) fluids to improve blood pressure.
At the same time, the stomach is decompressed by sedating the dog and passing a stomach tube to remove gas and stomach contents (if possible) or inserting a large needle through the walls of the abdomen and stomach to relieve gas pressure.
Once the dog has been stabilized, surgery is required immediately. During surgery, any additional gas or stomach contents are removed, the stomach is returned to its normal position, and the stomach, spleen, and other organs are examined for signs of tissue damage or death.
Any damaged or dead portions of the stomach are removed, and the entire spleen may be removed if it is compromised.
Lastly, a procedure called gastropexy is performed, in which the stomach wall is surgically stitched to the inner abdominal wall.
As the gastropexy heals, an attachment forms between the stomach and abdominal wall that prevents the stomach from twisting and causing another GDV in the future.
Without a gastropexy, there is up to a 75% chance that the dog will develop GDV again.
After surgery, dogs are hospitalized for several days for continued monitoring and IV fluids.
Pain medication and antibiotics are given for a few days following surgery. Dogs are not fed for 48 hours, and anti-nausea medications may be given to dogs that continue to vomit.
The overall mortality (death) rate in dogs with GDV is 25-30%. Dogs that experience symptoms for more than 6 hours prior to surgery, have abnormal heart rhythms before surgery, or require removal of the spleen or portions of the stomach usually have a worse prognosis for survival.
Dog Breeds at High Risk for GDV
Dog breeds most at risk for GDV include deep-chested large and giant breeds, such as the Great Dane, Saint Bernard, German Shepherd, Doberman Pinscher, Old English Sheepdog, Standard Poodle, Irish Setter, Gordon Setter, Weimaraner, and Basset Hound.
However, it is important to note that bloat and GDV can occur in dogs of any breed. Therefore, owners of any breed of dog who notice potential signs of these conditions should have their dog evaluated by a veterinarian immediately.
Preventing GDV in Dogs
Since the exact cause of bloat and GDV is unknown, it is impossible to prevent these with 100% certainty. However, some measures can be taken to decrease their likelihood.
Owner education regarding the signs of bloat and GDV is important, especially for owners of breeds prone to these conditions.
Owners of high-risk breeds may consider having a prophylactic gastropexy performed at the time of their dog’s spay or neuter surgery, which does not prevent bloat but may prevent the stomach twisting to cause GDV.
Dogs should be fed 2-3 smaller meals per day, rather than one large meal per day, and should not eat from elevated food bowls.
Feeding canned food or dry food without an oil or fat listed in the first 4 ingredients may help to decrease the risk of GDV.
Exercise should be restricted before and after meals. Importantly, dogs that have had bloat or GDV, or dogs with a parent or sibling that has had these conditions, should not be bred, as their offspring will also have a higher risk of developing GDV.